Triangulum, aka M33, is the second closest major galaxy - after the Andromeda Galaxy - at a mere three million light years. It's also generally considered the most distant object, though M81 (twkeve million light years away) has been observed by a few experienced observers, and of course there was an event earlier this year, which for a short time was a naked eye object at 7.5 billion light years. M33 is a good sized galaxy - third largest in the Local Group, which, of course, also include Andromeda and the Milky Way.
This is an APOD image. Click the picture to view the APOD page for it. Click the image on that page for a higher resolution view.